1. Field of the Invention
The present invention relates to laser engraving systems and engraving methods, particularly to a 3D (i.e., three-dimensional) laser engraving system and a 3D engraving method thereof.
2. Description of Related Art
Laser engraving is the practice of using lasers to engrave or mark an object/workpiece. A computer system is usually used to drive the movements of a laser in order to achieve precise and clean engravings. The laser engraving does not result in tool bits contacting the engraving surface. This is considered an advantage over alternative engraving technologies where bit heads have to be replaced regularly.
A laser engraving system for engraving a workpiece can be defined as two main parts: a laser and a controller. The controller controls the beam emitted from the laser to trace patterns onto the workpiece. The controller (usually a computer) controls the direction, intensity, speed of movement, and spread of the laser beam aimed at the workpiece. The workpiece is picked to match what the laser can act on.
Typically, there are three main genres of laser engraving systems. The most common is the X-Y table (i.e., two-dimensional (2D) laser engraving system) where, usually, the workpiece is stationary and the laser moves around in X and Y directions drawing vectors. Sometimes the laser is stationary and the workpiece moves and sometimes the workpiece moves in the Y-axis and the laser moves in the X-axis. A second genre is a 3D laser engraving system, particular for a cylindrical workpiece (or a flat workpiece mounted around a cylinder) where the laser effectively traverses a fine helix and the on/off laser pulsing produces the desired image on a raster basis. In the third method for 3D laser engraving, both the laser and workpiece are stationary while mirrors move the laser beam over the workpiece surface. Laser engravers use this technology in either raster or vector mode.
The third genre of the laser engraving system is suitable for engraving different size/shape of workpieces. However, the present laser engraving system can be very technical and complex. Thus, the system is quite expensive and is not easy to handle/operate.
What is needed, therefore, is a laser engraving system for engraving a three-dimensional pattern onto a workpiece and an engraving method thereof to overcome the above-mentioned shortcomings.